Ice-making apparatus



NGV. 12, 1940. l i T, I POTTER 1 v A2,221,594 v ICE-MAKING APPARATUS IFiled vApril 11, .1938

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v INVENTOR YZ0/m51'. Porn-R ATTORNEY Patented Nov. 12, 1940 UNITEDSTATES PATENT foFFlcE y 2,221,694 ICE-MAKING APPARATUS f Thomas I.Potter, Buffalo, N. Y.

Application April 11, 1938, Serial No. 201,246

4 Claims.

The present invention relates to improvements in ice-making apparatus,and more particularly to apparatus of the type in which ice blocks areformed at or near the bottom of a tank of water and then are releasedand floatedv to the surface of the Water. Y

In my copending application Serial No. 130,432, filed March 12, 1937, Idescribe an ice-maker of this general type which is connected into thel0 refrigerating circuit of a household refrigerator, operating on anintermittent cycle, the ice blocks being formed during the on period ofthe refrigerating cycle and being released and floated to the surfaceduring the off period.` Most household refrigerators operate on anintermittent cycle in which the on period is of suiiicient duration tofreeze the ice blocks and the off period is also of sufcient duration tofree the Y ice blocks from their molds. Obviously, however, theice-making apparatus described in said copending application would notbe suitable for use with a refrigerating circuit operatingcontinuously.y nor for one operating intermittently at such frequencythat the-on period would be too short to form blocks of ice or the offperiod too short to release the blocks. It is, therefore,`

an object of the present invention to provide an ice making apparatuswith an off and on control making it feasible to connect itsrefrigerating circuit in series or parallel with a continuouslyoperating refrigerating circuit or with van intermittently operatingrefrigerating circuit of comparatively high frequency.

One object of my invention is to provide an apparatus of this characterwith means for controlling the size of the ice blocks formed.

It is a further object of my invention to provide means for supplyingheat to the ice molds at proper intervals and in sufficient quantity toeifect a quick release of the ice blocks.

Another object of my invention is to provide automatically operatingmeans for interrupting the freezing of the ice blocks and releasing thesame from their molds.. Still another object is to provide thermallycontrolled means for this DUYPOSB- Other objects and advantages of myinvention will appear in the following description and claims.

In the accompanying drawing:

Fig. l is a plan view of an ice-making apparatus embodying thisinvention and attached to a household refrigerator, the latter beingshown fragmentally and in section.

Fig. 2 is a fragmentary transverse vertical sec- (Cl. 62-105) l tionalelevation thereof on an enlarged scale on line 2-2, Fig. l.

Fig. 3 is a central sectional View of an end portion of an electricheating element which may be used on my ice-making apparatus. 5

Fig. 4 is a transverse section thereof on line 4 4, 3.

Fig. 5 is a fragmentary longitudinal sectional elevation of another formof ice-making apparatus showing other means for releasing ice i0 blocksformed by means of the apparatus.

Fig. 6 is a sectional bottom plan view on line 6--.6, Fig. 7, of atime-controlled means for use in connection with my improved ice-makingapparatus and this figure shows diagrammatically 15 the electricalconnections between the time controlled means and other parts of theice-making apparatus.

Fig. '7 is an elevation of the time-controlled means shown in Fig. 6. 20

Fig. 8 is an elevation, partly insection, of a household refrigeratorhaving an ice block making device embodying this invention.

Fig.. 9 is a wiring diagram connecting the on and off control of the icemaking apparatus 25 with the thermostatic control of a householdrefrigerator.

In Fig. l, I show at I a portion of a household refrigerator which. itwill be understood, is

' equipped with a refrigerating system operating 30 either continuouslyor intermittently. I'he operating mechanism of this refrigerator and thecooling unit or units provided therein are not shown, but two pipes ofthe refrigerant circuit are shown at Il and I2 respectively. Pipe II 35may be on the high pressure sideof the circuit and pipe I2 on the lowpressure side. I have also shown in Fig. 2 a refrigerating machine orcompressor I3 driven by an electric motor I4, which may form apart ofthe refrigerating sys- 40 tem employed in connection with therefrigerator Attached to one of the refrigerator walls and on theoutside thereof, is an ice-making device incorporating one embodiment ofthis invention. 45 This device comprises an outer shell I5 and an innershell I8 between which there is a packing I1 of insulation material. Theinsulation material is supported under the shell I8 by the bottom wallof the shell I5.

The inner shell I6 which constitutes a water tank, is provided withsuitable molds for ice. These molds may be of any suitable form orconstruction and may be portions of the bottom of the tank I6. By way ofexample. I have provided the bottom of the water tank with depending icemolds preferably arranged in two rows, with the molds of onerowstaggered with respect to those of the other row. These molds are shapedso that when ice blocks are formed therein and released from adhesion tothe walls of the molds by melting, they will float to the surface of thewater in the tank. For example, the molds may be of inverted conicalform and are formed of metal having high thermal conductivity.

The molds in the'particular construction illustrated are refrigerated bymeans of a U-shaped refrigerant conduit or line, one leg 2| of which isconnected to one row of molds at the bottom thereof and the other leg 22to`the other row of molds. The conduit having these legs 2I and 22 maybe cut into the line I2 either in parallel or in series with the coolingunit of the refrigerator. In the embodiment illustrated, a seriesconnection is provided which may be either at the intake or the outletside of the cooling unit of the refrigerator I9.

Means are preferably provided for interrupting the freezing of water inthe molds 20 independently of the intermittent or continuous operationof the mechanism of the refrigerator, and this may be accomplished inany suitable manner. For example, as clearly shown in Fig. 2, I providethermostatcally controlled means for interrupting -the supply of currentto the motor I4 which operates the compressor I3. The thermostatic meansmay be of any suitable or desired construction, and as illustrated inFig. 2, this thermostat is provided with a bulb-like portion 24 arrangedin thermal contact or in heat conducting relation to one of the molds29. .The bulb-like portion 2li of the thermostat is connected by meansof a capillary tube 25 with an expanslble member or bellows 26. The bulbcontains an expansible fluid which when heated expands and in turncauses the expansion of the bellows member 28. The expansion of thismember is opposed by means of a coil spring 21, the pressure of whichmay be varied by means of an adjusting screw 28 so that the temperatureat which 'the thermostat operates the bellows 26 may be varied asdesired, and the regulation of the adjusting screw 28, consequently,also regulates the size of the ice blocks formed in the molds.

The thermostatic device described may operate in any suitable manner toactuate a current controlling switch so that when the portion of themold to which the bulb 24 is applied has a temperature of about 32 F. ormore, the bellows 26 will expand and move the switch into a position toclose a circuit to the motor I4. This will cause the refrigeratingapparatus to operate to freeze `ice in the molds 20. When the portion ofthe mold to which the thermostat bulb 24 is applied becomes chilledbelow the freezing point of water the action of the switch is reversedso that the supply of electric current to the motor I4 is interrupted. Ihave illustrated diagrammatically in Fig. 2 a double pole switch 30,-theblades of which are connected by means of conductors 3| and 32 to asource of power. The blades are mounted to swing into contact withstationary switch terminals to which the ends of conductors 33 and 3Qare connected. These conductors lead to the motor I4, .and consequently,when the bellows member 25 is expanded due to heating of the fluid inthe thermostatc bulb 24, the switch will be moved into position tosupply current to the motor I4.

In accordance with my invention. I also provide means for releasing bymeltage ice blocks formed' in the mold 29. This may be accomplished inany suitable or desired manner by supplying suilicient heat to the moldsto release the ice blocks and in the particular construction shown byway of example in Fig. 2, I have provided electric heating means forthis purpose. These electric heating means are arranged in heat transferrelation to leach mold and may be in the form of an electric resistancewire 31. This resistance wire 31 may be connected by means of conductors33 and 39 to two switch terminals which may also be engaged by themovable switch member so that after the switch member has opened thecircuit to the motor I4, it will be further moved into engagement withthe switch terminals to which the conductors 38 and 39 are connected.Current will, consequently, be conducted to the resistance wire to heatthe mold 20 sufficiently to release the ice block formed therein. Assoon as this is accomplished the heat from the resistance coil will alsoraise the temperature of the bulb 24 of the thermostat so that themovable switch member 30 is again moved into position to supply currentto the motor I4. Since the thermostat may be set to operate ontemperature differences of comparatively few degrees, it follows thatthe heating of the molds will be interrupted immediately after releaseof the ice blocks. so that no unnecessary heating of the water in thetank results.

The electric heating means may be of any suitable construction. I havefound, however, that a very satisfactory heatingunit can be formed asshown in Figs. 3 and 4. In these figures, the electric resistance wire31 isshown as having a covering 49 of suitable electric insulatingmaterial such, for example, as woven asbestos. This insulated heatingwire is drawn .through a small metal tube 4I which may, for example, beof copper and which may be soldered or otherwise arranged in good heatconducting relation to the molds 20. While asbestos* is also a heatinsulator, yet since it forms a comparatively thin layer about theheating wire 31, it permits sufficient heat to pass to the copper tube4I 'to quickly release an ice block from a mold. The ends of the tube 4Imay be sealed in any suitable manner to prevent moisture from enteringthe interior of this tube. For this purpose, I provide at each end ofthe wire a suitable sleeve 42 having an enlarged end which may be filledwith a suitable ceramic or refractory cement 43 through which the endofthe conductor 31 extends and which excludes moisture from the interiorof the tube 4I. To the ends of the heating wire 31, low resistanceconductors may be connected, the two ends of the heating wire beingshown connected to the conductors 3B and 39. The heating elementdescribed is desirable in that it prevents short circuits, which mightbe caused by moisture collecting on the outer surfaces of the molds, due

to condensation. Any other electric heating means for the molds may, ofcourse, be employed, if desired; As clearly shown in Fig. 2, the entireouter surfaceof the mold 20 is surrounded with the heat insulatingmaterial I1.

In Fig. 5, I have shown other means for releasing the ice blocks fromthe molds through.

meltage, which may also be operated electrically and automatically. Inthis construction, the outer shell I5 arranged about the tank I6 isprovided with abottom wall 45 through which at least portions of themolds 20 extend. Below this bottom wall is formed a compartment or spaceal l , from` the air to the molds.

in' which air may be circulated to provide sufcient heat to release theice blocks from the molds by meltage. In the construction shown, ahousing 46 is provided below the bottom wall 45 of the shell i and thishousing may, if desired, contain a drip pan 41 in which water ofcondensation from the outer surfaces of the molds may be collected. Themolds also may be provided with radiating fins or ribs 48 of anysuitable or desired form to facilitate the transfer of heat The airhousing 46 is provided with any suitable air inlet 56 and. with an airdischarge opening 5| and a positive circulation of air through the airhousing is provided in any suitable manner, for example, by means of afan or blower 52 driven by an electric motor 53. The fan, in theconstruction shown, is arranged at the inlet opening 56 and the outletopening 5| is so arranged that the air passing through the housing willcontact with all of the molds, to ensure quick release of the ice blocksin all of the molds. The molds 20 are connected with a conduit 54 forrefrigerant in any suitable manner, for example, as described inconnectionv with the molds shown in Figs. 1 and 2.

In the operation of the construction shown in Fig. 5, the circulation ofair through the air housing 46, to release by meltage ice blocks formedin the molds 20, can be controlled in the same manner as described inconnection with the electric heating units shown in Figs. 2 to 4, namelyby connecting the fan motor 53 to the conductors 38 and 39 in place ofthe electric heating units shown in Fig. 2.

Bymeans of the construction shown in Fig. 5, air is circulated throughthe housing 46 only when it is desired to remove the ice blocks from themolds by meltage, at which time the fan 52 provides for an ample flow ofair through the housing 46 so that the ice blocks may be readily removedfrom the molds. During the freezing of the ice blocks in the molds, thefan is standing idle, so that there is very little or no circulation ofair through the housing 46, and consequently, the air contained in thehousing 46 becomes chilled and does not interfere with the freezing ofthe ice blocks in the mold.

In Figs. 6 and '7, I have illustrated an arrangement whereby thethermostatic control of the ice-making apparatus may be replaced by timeor clock controlled means. 60 represents a clock which may be mounted onany suitable xed support 6i which may, for example, be a part of theouter shell of the ice-making device or of the refrigerator. The clock66 drives a contact arm 62 fwhich bears against a -commutator or circuitopeningand closing device 59 having a. contact segment 63 which is.electrically connected by means of aco'nductor 464 with one terminal ofa solenoid 65. The other terminal of the solenoid may be connected toone of a pair of power lines 66 and 61, for example, the line 66, theother line 61 being connected with the contact arm 62. Consequently,when the contact arm 62 engages the segment 63 the solenoid will beenergized so that a core 18 thereof will be drawn into the solenoidagainst the action of a coil spring 1I. This core is connected to amovable switch member 12 having two blades which are connected.respectively with the power lines 66 and 61 by means of conductors 13and 14. When the solenoid is energized, the switch member 12y will bedrawn into circuit closing position in iwhich the blades thereofcontact-with termi-nais connected with conductors T5: and 16 leading toa motor 11 which -driyes the compressor of the refrigerating apparatus.When the contact` arm 62 moves out of engagement with the segment 6l,the solenoid will be de-energized and the spring 1| will move the core10 outwardly, thus moving the switch 12 out of engagement with theterminals of the conductors and 16 and thus interruptingy the supply ofcurrent to the driving motor 11 of the compressor.

If the contact arm 62 is driven in counterclockwise direction indicatedby the arrow in Fig. 6, the end of the contact arm 62 will contact wit',the insulation of the commutator 59 for a brief period of time aftermoving out of contact with vthe segment 63, and will then contact'withanother segment 86 also arranged on the commutator 59. 'Ihis segment 86in the construction shown in Fig. 6 is connected by means of a conductor8| to suitable means for heating the molds to release the ice blocks. Byway of example, I have shown in Fig. 6 a series of electric resistancewires 82, corresponding to the resistance wire 31 described inconnection with Figs. 1 to 4. The other terminals of these resistancewires are connected by means of a conductor 83 to the line 66, so thatif a switch 84 arranged in the conductor 83 is closed, a circuitincluding the heating coils 82 will be completed through the contact arm672 and segment 86 to the other line 61'. After the contact arm 62 movesout of engagement with the segment 80, it will again contact with theinsulating surface of the commutator 59 for a short period of time,whereupon it will again contact with the segment 63 to start theoperation of the refrigerating system. The segments 63 and 80 mayextendin the path of movement in the contact arm 62 to'any suitable ordesired extent, depending upon the length of vplace of the heating coils82 and if the airvheat- .ing of the molds as shown in Fig. 5 isemployed,

the electric motor 53 may be substituted for the heating coils 82 sothat the clock controlled mechanism may provide current to the electricfmotor'53 when the movable contact arm 62 engages the segment 86.

While I have illustrated in Fig; 1 an application of my improvedice-making apparatus to a household refrigerator of ordinaryconstruction, yet it will be obvious that it is not intended to limit myimproved ice-making. apparatus to use as an adjunct'or accessory to ahousehold refrigerator, for the reason that, if desired, my inventioncan readily be applied to a refrlgerating apparatus which serves solelyto produce ice blocks. By way of example', I have illustrated anapparatus of this type in Fig. 8.

This refrigerator includes acabinet 96 having a lower compartment 9|containing any suitable type of heat pumping unit. -This unit maycomprise a motor 92which drives a compressor- 93.

represents a condenser which receives and condenses the refrigerantcompressed byv the compressor 93 and discharges the liquefiedrefrigerant to a receiver 95. A high pressure line 96conveysf'reirigerant from the receiver 95 to a suitable conduit orconduits 98, which are in ther- .0 ring relation to said mold andconnected with mal contact'or heat transferring relation to a series ofmolds 99 in the base of a tank |00 arranged in the upper portion of thecabinet. The conduit or conduits 98 may be connected to a return pipe|0| leading to the compressor. |03 represents electric heating coilsalso arranged in heat conducting relation to the molds 99 for releasingthe ice blocks formed in the molds. 'I'he operation of this cabinet may,of course, be automatically controlled by any of the means hereindescribed and the electric heatingcoils may also be replaced by the moldheating means shown in Fig. 5. tank |00.

In Fig. 9 I have disclosed a wiring diagram showing the contacts of theon and off control switch 30 of the ice making apparatus connected inseries with the contacts of the diagrammatically illustratedthermostatically controlled switch |05 of a household refrigerator.During the on period of the on and oif" switch 30 of the icemaking'apparatus, the thermostatlcally controlled switch |05 of therefrigerator controls the intermittent operation of the compressor motorin the normal way. This control of-the motor will be interrupted andsuperseded by the on and off switch 30 when it opens the motor circuitand closes the ice block releasing circuit but only for the short timenecessary to release the ice blocks. After the ice blocks have beenreleased the motor circuit will again 4be closed by the on and offswitch 30 and the motor will again-operate intermittently under controlof the thermostatically controlled` switch |05 in the refrigerator.

For the purpose of freezing ice when the refrigerator is cold andrequires no refrigeration, I provide a hand switch |06 to shortcircuit'the thermostatically controlled switch |05 of the refrigeratorand to place the motor under control of the on and olf switch 30 of theice making apparatus.

While I have described a preferred embodiment of my invention andcertain modifications thereof, it will be understood that these are tobe taken as illustrative and not limitative of my invention and that Ireserve the right to make various changes in form, construction andarrangement of parts without departing from the spirit and scope oi' myinvention as pointed out in the following claims.

I claim as my invention:

1. An ice-making apparatus adapted to be used as an Aadjunct to arefrigerating system having a refrigerant circuit operating on anintermittent high frequency cycle, said apparatus comprising a watertank provided with thermally' insulated walls and formed with anice-block mold, a refrigerant conduit extending into heat transfer- |04represents a lid or cover for the waterv said circuit to pass at least apart of the refrigerant through said conduit, means for interrupting theflow of refrigerant through the conduit, time controlled means forintermittently actuating said interrupting means at relatively lowfrequency such that each interval between interruptions will include aplurality of operating periods of said intermittent cycle, meansvadapted to lead a current of air from the outside atmosphere in contactwith said mold, and a controller for said air currents.

2. In an ice-making apparatus including a cooling circuit, and arefrigerating system for circulating refrigerant in said coolingcircuit, said apparatus comprising a water tank provided with an iceblock mold in heat transferring relation to said cooling circuit, athermostatic member responsive to changes in temperatures of a part ofsaid ice block mold, means actuated by said thermostatic member forstarting and stopping said rei'rigerating system, and means forsupplying heat to said mold and which are actuated by said thermostaticmember when the operation of said refrigerating system is interrupted.

3. In an ice-making apparatus including an electrically drivenrefrigerating system for circulating refrigerant in a coolingcircuit,.the combination of a water tank provided with an ice block moldin heat transferring relation to said cooling circuit, a thermostaticmember responsive to changes in temperature of a part of said ice blockmold, electrically operated means for supplying heat to said mold torelease an ice block formed thereon, and electric control means actuatedby said thermostatic member for simultaneously interrupting the supplyof electricity to said electrically driven refrigerating system and tosupply electric current to said electrically operated heat supplyingmeans to release by meltage an ice block formed onsaid mold.

4. In an ice-making apparatus including an electrically drivenrefrigerating system for circulating refrigerant in a cooling circuit,the combination of a water tank provided with an ice block mold in heattransferring relation to said cooling circuit, a thermostatic memberresponsive to changes in temperature of a part of said ice block mold,an air chamber into which at least a portion of said mold extends, ablower for directing a current of air through said air space, anelectric motor for driving said blower, and electric control meansoperated by said thermostatic member for simultaneously interrupting thesupply of electricity to said electrically driven refrigerating systemand for supplying electricity to said electric motor for driving saidblower, to release by meltage an ice block formed on said mold.

THOMAS I. POTTER.

